Where freepbx store extension's Outbound CID?

if you create a new extension in freepbx you can define Outbound CID which is nice and useful. the strange thing is that this number is not stored anywhere in /etc/asterisk/ it’s only stored in mysql’s users table even after apply changes pushed. so how can astersik use and know what is Outbound CID for a given extension if it’s not stored in any config files??? or where is it stored?